Oh, Brother
by Critterz11
Summary: It was unexpected, for both of them. But, in time sometimes family trees grow out some new branches. Izuku Midoriya and Katsuki Bakugou must both cope with one of the biggest unexpected surprises in both of their families: The arrival of a new baby sibling for each. Toshinori/Inko and Masaru/Mistuki. Some Izuku/Bakugou BroTP/friendship moments also bond to happen.
1. Prologue: Izuku's News

It had started about five years ago. I was thirteen then, and struggling my way to fit into society was hard. But, in time, I made it through and that was thanks to Toshinori Yagi, aka, "All Might". Yep, my childhood idol and hero helped me through my toughest times. Who would've expected that? And who would've also expected in time he would become part of my own family as a whole? I sure didn't. My name is Izuku Midoriya, some people call me "Deku"...like, "you can do it". And this is the story of how I actually became a big brother. And, well, I wasn't the only one who became a brother at the time too, but I'll save that for a later time.

This actually started about nearly three years ago, when I was only fifteen. I'm eighteen now. Sure, Toshinori had trained me hard and I had endured some challenges being accepted at one of the biggest hero community schools in the nation: U.A. High. But, lately I had taken notice that my mentor himself was becoming a bit more closer than I thought. I met up with him one day after a training session with my two closest friends and allies, Tenya Iida and Ochako Uraraka.

"Midoriya-san, my boy...how was the training session?" Toshinori called out, once he caught my attention.

"Oh, it went...as normal Toshinori-sama." I responded, wiping a sweat calmly from my head. I was getting stronger it seemed with every new day, but still, a little sweat and burn never killed to release itself.

"I'm glad." Toshinori added, giving a smile. "It amazes me how much you've experienced in two years alone, Midoriya. From that day the League of Villains attacked the simulation joint, to your run-in with the assassin Stain while training with Torino-sama. You've truly endured a lot in such a short time."

"I know, Toshinori...I know..." I added. I knew he was complimenting me, because I had stayed strong threw all of what had happened. But, still, in just two years alone all that happening felt like a rush in my head to remember. "Anyways, sorry if it's a hunch, but was there anything else you wanted to speak about?" I asked Toshinori.

"Actually yes..." Toshinori returned. "Though I figured your mother had spoke to you about it already..." I was confused, I thought for a moment what mom had told me this morning before I headed off to school. Was there something important she wanted me to keep in mind? Because, I felt awkward trying to remember.

"Oh, she must've not spoken on it." Toshinori added, reassuring me to take a breather of relief.

One thing that was on my mind though was also the fact Toshinori and my mom had been...going steady with a relationship. My mom and Toshinori had met some time before, especially when he had to confess the word out he was my mentor and that all the struggles through wounds using my inherited quirk had caused my mom to become fearful. Of course, in the end Toshinori pleaded with all his heart for me to keep training as a hero, especially with how he wanted the best for not only me, but, not for my mother to fear herself. Even if times were tough, I was still comforted that I was going to stay strong. Anyways, what had happened was just a few months back at the end of last year, when Toshinori and my mom decided to start hanging out together. My idol is a tough guy for sure, but, like me he has a sensitive, emotional nature as well and needed someone to talk to for some comfort. My mom, with open arms, was happy enough to consider doing so. From there, on every weekend both of them would start going out for date nights and enjoying each other's company. It was then, I noticed, my mom was in love with Toshinori.

"We can talk about once we get back..." Toshinori added, as we continued walking along to take the bus back home. I nodded, still curious what he was trying to inform me of.

Once we arrived back at the apartment, I was warmed with the hugs of my mother's affection, of course. My mom, Inko Midoriya, was a selfless, caring and devoted soul with a pure heart. Some time before I was even born, she had married a man, my biological father: Hizashi Midoriya. Dad happened to just disappear one day when he was called with other pro-heroes for overseas work at a major operation. According to Mom, she never saw him again and feared he had died or went missing. Since then, she took every effort and task to being a hard-working and supportive mom to me in my early childhood. My mom isn't really a superhero, but she does have a gravitational pull in her quirk that allows her to attract objects from a distance. She takes on helping at community centers for the weak or disabled as a job, so, my mom is considered a hero to them. Heh, she's also a hero to me for all her love and support. Anyways, once she finished hugging me I had the question on my mind.

"Mom...was there something you wanted to tell me earlier?" I asked, curious. She gave me a warm smile, holding my hands softly in her own.

"Izuku...sweetie, this is big so please stay calm for what I am about to explain." My mom began to speak warmly. "You know Toshinori-san and I have been...dating for a while now, and sometimes, things happen, right?"

"Yeah." I added, nodding. I had known there was a relationship building, but was there something more she wanted to inform me on.

"Izuku...I'm...I'm pregnant." Mom added next. "Toshinori and I, well, you're old enough to understand we had an affair and well...I'm going to have a baby. We're going to have a baby, me and Toshinori."

"You mean?...I'm going to be a big brother!?" I questioned in shock, surprised. My eyes were widened hearing those words, a slight flushed expression on my face. I was sweating like a candle being boiled, my pulse jumping a bit.

"Yes...but...don't be afrai-" My mom added before she was cut off by me giving a soft hug. She knew immediately, from my smile and my tears, I was overwhelmed with joy. Mom gave me a soft, reassuring pat on the shoulder as she giggled. Toshinori grinned and chuckled a bit himself.

There was so much going on at that moment hearing that, but, I was filled with so much love and excitement on what was to possibly come in the following months.


	2. Chapter 1: Harshness

Note: This chapter is from the character perspective of Katsuki Bakugou.

"WHAT!?" I screamed at the top of my throat, angered. Boiling mad was what I was, upon hearing the words "You're going to be an older brother" come out of my mother's mouth. I growled, clenching my fist.

"Now don't you start that aggressiveness with me, young man!" Mom shouted at me, pointing a finger in my face. "It was unexpected for both me and your father yourselves that this would've happened."

"Oh, because Dad was too much of a pussy to even consider wearing a frigging condom!?" I snarled, looking over at Dad. Dad was a nervous wreck of a man, so he just fell onto his knees, sobbing in reaction.

"Katsuki Bakugou, you will not speak to your father or anyone along those lines with that sort of language, you hear me?" Mom growled again. "If anything, you should feel proud on the idea of your family and showing you do care for them." She was huffing, sweat glistening across her irritated, blushing face.

"The only thing I'd feel proud of...is you'd get an abortion, you old hag!" I returned disruptively in my tone at it, snarling more. That's when it struck me.

"WHACK!"

Mom slapped me hard on the cheek, the imprint burning right into my fair skin. I retracted a bit, rubbing my cheek with a scowl.

"That's it! Go to your room, if you don't have anything nice to say, DON'T SAY IT AT ALL! Go! Now!" Mom ordered, pointing me to exit the room at once. She looked over at Dad, trying to comfort him. As I stomped away, I could make out the both of them, teary-eyed and emotionally torn a bit with sobbing and sadness. I just rolled my eyes and huffed as I went upstairs into my room. My room was the typical kind of place you'd expect an arrogant jerk to chill out in. Grungy laundry lined along the floors and bed, Metallica and Five Finger Death Punch posters on the walls, a punching bag with my crudely-drawn rendition of that "Deku" dork on it. Climbing onto my bed, I just laid-down, face-first grumbling into my pillow.

I kept thinking to myself. Why? Why did my parents have to go and make another one. Wasn't I enough? Did they secretly hate me and felt I was a trashy failure? Because, that's sure as heck was what I was thinking in my mind. I wasn't even the nicest, caring individual ever so the chances of another child being around me would've been fatal. Even innocent kids out on the streets noticing me, I tend to scare off in a single growl of my throat. There were many unanswered questions in my head, but, yet, the strangest thing I was beginning to question. Why, of all things, was I crying?

Stumbling around, not wanting to get off the bed I searched for my phone and took it upon my hands. I needed to vent to someone, the only person I felt some aspect of respect and friendship with. I dialed the number for Eijirou Kirishima, waiting for him to pick up. "Come on...spiky hair..." I muttered to myself, wiping the corner of my sobbing left eye.

"Hello?" A voice responded on the other end. It was Kirishima.

"Hey..." I continued on, trying to hide the emotional grief and resentment in my tone.

"Bakugou-san...are...you crying?" Kirishima responded, concerned.

"No..." I sighed. "Yes. Let me explain. Mom and Dad told me they found out they are having another child..."

"Oh, wow, congratulations Baku-bro!" Kirishima exclaimed, a bit optimistic. I was alright with him calling me that at times, and it didn't also surprise me that'd enlighten his mood given Kirishima was the eldest child of a few younger siblings. All of which loved and looked up to him.

"No, no, I'm not okay with this!" I huffed. "I got mad...and well, I said some things...". My throat was coughing sore, and my eyes were rubbed out dry and irritable.

"Oh...I see..." Kirishima responded. "Maybe you should go and talk to them? I'm sure your Mom and Dad would know this was a misunderstanding."

"It's not just that, Kirishima!" I added. "I feel like they're having another kid because...I'm a failure." I moaned, still upset and furious at myself.

Kirishima's tone turned soft, and concerning. "Bakugou...you're not a failure. Your parents love you with all their heart and soul. They've always been there when you needed them, and least expected it. Besides...if they hated you they would've thrown you out like trash on the streets, letting you fend for yourself in the harsh, cold darkness of the wild." I was still grumbling, trying to calm down at least a bit. What I was not aware of, was Mom was overhearing me outside of my room.

"I sure feel like I am one honestly." I returned to Kirishima. "I thought I could truly be a great person, but it seems I'm nothing but arrogant, pathetic, selfish and cruel...and that's just how the world sees and feels about me. I'm a big...frigging...loser!" I huffed, blowing out air of my brightened, flushed nose.

"Bakugou, you're not-" Kirishima was about to speak, before I pressed my thumb to end the call session. I shut off the phone, placing it on the nightstand and just grumbled, tucking my face into the pillow more. The door to my room slowly creaked, as someone approached.

"Katsuki..." Mom spoke to me, in a more comforted, calming and concern tone of voice.

"Go away..." I muttered, muffled by my pillow's cushion. "Just...let me be, okay?"

Mom still sat there, rubbing her hand softly through my hedgehog-like protrusions of messy, spiky hair. "Okay..." She added. "But, if you do want to talk, just come find me alright?" She kissed me softly on the side of my head, I just rolled my eyes, irritated. Once she was gone, I decided to just keep there, calmly breathing and trying to regain some self-dignity. I hated to admit it, but, she was right. I did need to talk further on this matter in a more approachable manner.


	3. Chapter 2: Esteem

Oh man, the news about Mom and All Might stirred about in my head the rest of the evening. Just, hearing about that I was going to be a brother left me shocked, but with a positive charge on the other end. I was excited for sure, and wanted to take the time given as it'd be a few more months to prepare myself and study up on brotherhood. We were eating dinner that night, the three of us all together: Mom, Toshinori and myself.

"So, you and Toshinori...it's really?" I kept asking to them, knowing the answer in honesty. It was just still a big surprise to me, I didn't want to stop talking or thinking on it.

"You're really thrilled about this, I presume Izuku?" Mom responded, lightly laughing with a smile. I nodded my head, my lips touched ear-to-ear in a beam.

"In honesty yes...but, at the same time I have some questions, and maybe a suggestion or two..." I spoke honestly, rubbing the back of my neck. They were both open to hear me say what I had on my mind. "Do you think, well...if you're extending on a family, that, you two should get married as well?" My face was flushed a bright pink, embarrassed that the question could've come out quite out of context. They were quiet for a second, but then lightly smiled and laughed.

"Midoriya my boy, you really think a lot like your mother. And that's a good thing." Toshinori added, beaming a smile of reassurance at me. "Yes, we're planning on the engagement within the next month or two." He added.

"It'll be a small ceremony, just between some mutuals and close friends." Inko added. "You could even ask your friends to attend if they want." That stirred in my mind for a minute or two, or maybe three. It'd be nice to have my buddies join in on the ceremony as guests, even though it'd have to keep low. Ochako and Tenya, among the others, still didn't suspect or know Toshinori and All Might were the same identity.

"You know what...yeah, I'll let them know." I finally added, smiling. We all agreed, continuing to enjoy our dinner at the same. Afterwards, it was getting a bit late, so I was going to check in for some rest. I got into the shower, scrubbing and rinsing myself clean, then brushed my teeth and put on a pair of my comfiest, yet casual pajamas. Really nothing more than a light grey t-shirt with a slightly-darker, but faded grey boxer shorts. As I got into bed, I took notice of Toshinori at the doorway.

"It's hard to believe we're actually now a family bound together, isn't it kid?" He spoke, with that typical smile on his uneven, yet sparse face.

"Yeah..." I muttered, awkwardly. "...First you're my childhood hero, then my mentor, and now...my step-dad basically, Toshinori-sama."

"Don't get worked up, boy." He added. "It'll all work out. It's like taking steps up the stairs, one foot in front in another. Progress." I agreed there with him, understanding beyond his metaphor there was a point. "Now, get some rest and we can talk more in the morning, alright?"

"Right." I spoke, getting comfy onto my bed with a book for some light pre-sleep reading. "Oyasumi-nasai, Toshinori-sama."

"Oyasumi-nasai, Midoriya-san." Toshinori added, before heading off. I read for a bit, then tucked in for some shuteye.

The next morning, I headed out with Toshinori to do some tasks with grocery shopping. We got freshened up and dressed, heading to the store to pick up the few things that were jotted down on the list Mom had informed us.

"Alright, we'll need some eggs, skim milk, oatmeal, cleaning supplies...and a few other things." Toshinori informed, as we got the shopping cart.

"Skim, or almond?" I questioned for a second. "Mom sometimes really likes almond, especially for the vitamin value."

"We'll get both then." Toshinori added, smiling. "We'll split for the skim, and Inko can have some almond sweetness." I smiled, returning the nod of my head softly. As we browsed about, picking up the goods, I happened to run into a good friend of mine, who was out on the same task of picking up essentials.

"Oh, Deku!" The girl in front of me, spoke, with a rather cheerful tone. It was Ochako Uraraka, Ochako, she was a very close friend to me since the first day I arrived at U.A. High and we've grown a lot since then together. To be honest, I was a bit smitten for her despite the fact our relationship was just strict friends. This weird hunch also came upon me she felt the same way, given she'd become flushed or lightly embarrassed at times.

"Ohayou, Uraraka-chan." I commented lightly, with cheer and bliss in my soul. "Just...picking up some supplies for the week. You?"

"Same." Ochako giggled. "Just a few light things though, Mom and Dad already got the grocery shopping done on a earlier day in the week." The auburn-haired girl with light brown eyes and soft pink cheek-like markings caught a glimpse aside me. "Oh, Toshinori-sama, I see you're with Deku-kun as well. My apologies for interrupting." She folded her hands, softly bowing.

"It's quite alright, Ochako." Toshinori spoke, reassuring her. Ochako gave a soft smile, curious herself at our rations in the basket. Her eyes turned down, as she noticed a soft-covered book among the food and supplies.

"Sorry to interrupt out of curiosity, but, why do you have a baby book, Deku?" She asked me, questioned. I became flushed, tugging at the collar of my shirt to release a cloud of steam.

"W-well...you know...um..." I muttered, stumbling to get a proper statement out. Ochako just blinked, confused, as her brows rose beneath her forehead and soft bangs.

"You can tell her, Midoriya-san." Toshinori chuckled, lightly.

"Alright...Ochako, Toshinori-sama and my mom, well, they're getting engaged and are expecting a baby." I spoke out, taking a deep breath afterwards.

Ochako literally squeaked with excitement, clenching her fists happily as she giggled. "Oh my gosh! Congratulations Toshinori-sama, and Mrs. Midoriya...and you too, Deku!" She cheered upon, speaking lightly not to cause too much of a distraction to other people shopping around. "You're gonna be a ni-san, Deku. I think you'll be a great one, with your motivation, support and loving knowledge and care for others." Ochako was speaking, very optimistic. I flushed a bit more, sweating and rubbing the back of my neck. "Anyways, I'll let you two get back to picking up things and myself as well. "Once again, congrats!" She added, excitedly as she got back to her task at hand.

I might have been seeing things, but, it felt like I saw Ochako blow a light kiss from her hand on the way out. I smiled, my face still tinted a bit with a light pink blush.

"You really like her more than a friend, do you?" Toshinori asked, in a confident manner.

"M-maybe..." I stuttered, then breathed softly. "Yeah, I do. But, I'll tell her and be honest when the moment is right. Let's just continue shopping, Toshinori-sama."


End file.
